The pipelines are commonly used for transportation of crude oils, usually used steel pipes of different diameters for this purpose.
Because the terrain features that are installed the pipelines, as well as fluids that are managed, it is necessary to protect materials of construction of the pipelines, both external and internal surfaces. With regard to internal corrosion, it is usually caused by contaminants in the crude oil, such as hydrogen sulfide, carbon dioxide, organic acids, water, minerals, suspended solids, asphaltenes, paraffins and microorganisms. Common ways to mitigate the damages include mechanical cleaning and the use of different chemicals such as corrosion inhibitors, scale inhibitors, biocides and dispersants.
The main damage caused by internal corrosion is uniform wear of the material, mainly due to the formation of iron sulphides and chlorides.
Globally and in México, there is a tendency of increasing the production of heavy crude oils, which generally have a higher content of pollutants.
Corrosion taking place in environments exposed to liquid fuels is a function directly related to the concentration of organic acids, organosulfur compounds, emulsified water and oxygen-rich environment. All of these factors together determine how aggressive this system can be.
Because of this, the global trend in the area of chemicals is the development of corrosion inhibitors with a greater degree of versatility to be able to control the corrosion levels despite significant increases in contaminants in the oil and fuel oil, which makes them more aggressive.
Most corrosion inhibitors used in the oil industry are organic compounds. The composition and chemical structure of the inhibitor significantly depend on the environment to which it will be immersed, is how they have the means in which the majority is water composition in which the organic phase is higher.
A variety of organic and inorganic compounds have been used to control corrosion in different aggressive media. Thus for packages employing aqueous based organic phosphonates, while for environments where the presence of hydrocarbons predominantly inhibitor use film base amino compounds, alcohols and imidazolinic compounds is a common practice.
Film corrosion inhibitors are usually composed of two parts: A polar electron-rich to be able to adhere to a metal surface through a coordination bond and a hydrophobic part that can be efficiently repel contaminants in the aggressive medium.
It is very important that the corrosion inhibiting composition does not emulsify water due to problems such as corrosion in pipelines and storage tanks or equipment failures and internal combustion engines.
Prior processes for obtaining N-alkyl or N-alkenyl or N-aryl beta-amino or imino propionic acids include:
U.S. Pat. No. 2,195,974 (Process for the production of new amino-carboxylic acid) discloses the development of new compounds such as N-alkyl or N-alkenyl or N-aryl beta-amino or imino propionic acids are produced from alkyl or alkenyl or aromatic amines and acrylic acid with water as a solvent with or without alkali metal bases.
U.S. Pat. No. 2,468,012 (beta-amino propionates) discloses the process of obtaining N-alkyl beta amino propionic acids produced from alkyl amines and esters of acrylic acid in the absence of solvent and subsequent neutralization with a alkali metal base.
U.S. Pat. No. 2,816,911 (Process of preparing N-alkyl-beta-alanine) discloses the process of obtaining N-alkyl beta amino propionic esters, which are produced from alkyl amines and esters of acrylic or methacrylic acid, in the absence of solvent, in a temperature range from 50 to 120° C. and subsequent neutralization with an alkali metal base.
U.S. Pat. No. 5,922,909 (Process for the selective control of amphoteric, zwitterionic compositions) discloses the process of obtaining N-alkyl or N-alkenyl or N-aryl beta-amino or imino propionic acids produced from alkyl or alkenyl or aromatic amines with beta-unsaturated acids in the presence of water in a pH range of 4.0 to 7.0, controlled by the addition of alkali metal bases or organic and subsequent neutralization with acid.
The use of corrosion inhibitors for ferrous metals in the transport and storage of liquid fuels include:
U.S. Pat. No. 4,214,876 (corrosion inhibiting composition) discloses the development of a formulation of the corrosion inhibition for ferrous metals exposed to hydrocarbon fuels made from 75 to 95% of an unsaturated aliphatic carboxylic acid of 16 to 18 carbons and 5 to 25% monoalkenyl succinic acid with a chain from 8 to 18 carbons, and their use as a solvent hydrocarbon compounds.
U.S. Pat. No. 4,509,951 (Corrosion Inhibitor for alcohol-based fuels and gasoline-alcohol mixtures) discloses the development of a formulation of the corrosion inhibition for ferrous metals exposed to liquid motor fuels based on alcohol-gasoline blends alcohol consisting of aliphatic carboxylic acid polyunsaturated 18-carbon, and the reaction product of a polyamine with an alkenyl mono-unsaturated aliphatic carboxylic acid of 18 carbons or alkenyl succinic anhydride from 8 to 30 carbons.
U.S. Pat. No. 4,511,366 (Liquid fuels and concentrates containing corrosion inhibitors) discloses the development of a formulation of the corrosion inhibition for ferrous metals exposed to liquid alcohol-based fuel or gasoline-alcohol mixtures consisting of aliphatic carboxylic acid poly-unsaturated 16 to 18 carbons and a polyamine alkenyl.
U.S. Pat. No. 4,737,159 (Corrosion inhibitor for liquid fuels) discloses the development of a formulation of the corrosion inhibition for ferrous metals exposed to liquid hydrocarbon fuels made from 35 to 70% by weight of a monoalkylene succinic acid with a chain ranging from 8 to 18 carbons and 30 to 65% of aliphatic or cycloaliphatic amine containing from 2 to 12 carbons and solvents and aromatic hydrocarbon compounds alcohols of 1 to 4 carbons.
The use of corrosion inhibitors for ferrous metals used in the processing of crude oil include:
U.S. Pat. No. 3,629,104 discloses the obtaining of organic acid salts of basic compounds derived from 1-aminoalkyl-2-alkyl imidazolines and their use as corrosion inhibitors for ferrous metals in acidic characteristic of the oil industry. The efficiency of corrosion inhibition of these compounds was evaluated by gravimetric techniques.
U.S. Pat. No. 4,450,137 discloses a composition characterized by the presence of a mercaptan or polymercaptan group, an amido group or polyamide, and the use of this composition as a corrosion inhibitor for acid media.
U.S. Pat. No. 5,062,992 discloses a corrosion inhibiting formulation for oil and water systems, wherein the formulation is resistant to sludge formation and tends to stabilize oil in water. The corrosion inhibitor includes an imidazoline dissolved in an aromatic solvent, a 2-hydroxy alkyl carboxylic acid and glycol. The imidazoline is preferably prepared from the reaction of a long chain fatty acid and a polyamine in a molar ratio of 1.5:1.
EP 526,251, A1 discloses the production of corrosion inhibitors from the reaction of compounds 1-aminoalkyl base 2-alkyl imidazolines with acids or unsaturated organic esters.
U.S. Pat. No. 5,415,805 discloses a composition and method for inhibiting corrosion of ferrous metals that are in contact with aqueous systems containing sulfur compounds. Composition comprises an aqueous solution of an alcohol, an organic acid, a fatty imidazoline, an ethoxylated fatty diamine and an aqueous solution of compound of molybdenum.
U.S. Pat. No. 5,785,895 discloses a method for inhibiting corrosion in aqueous media. The method involves incorporating into the medium an amount of corrosion inhibitor sufficient to inhibit corrosion. The corrosion inhibitor comprises an N-ethoxy-2-imidazoline. The N-ethoxy substituent is comprised of one to thirty ethoxy units and the substituent at the position 2 can be a polyunsaturated fatty chain formed from six to thirty carbon atoms. If the medium is fresh, the inhibitor also be constituted of a phosphorus ester derived from a oxyethylated alcohol soluble in water.